Spark plug



NOV. 8, 1927. 1,648,449 E. DIETzE SPARK PLUG Original Filed Oct. 11. 1925 Patented Nov. 8, 1927.,Y

EMIL'` ninrzn, 0F nicriiiioivn Him., newYoia'in` ASPARK Selina@ Application flied o'vctober i1, 192e, sei-rarit. set/,811,

' Thisinvention relates, generally',rto iinvprovements in ignition: `spark-plugs .1or' internalcombustion. engines; and, the invention: has rete-rence, more particularly, to a 5 construction of spark-plug provided VWith a novel arrangement of electrode 4inembersdesigned to V'furnish' a multiple spark-gap whereby the intensity of 'the sparks are greatly increased, and other advantages are 1U obtained as vwill subsequently appear.

'The invention has lorits principalobject to provide a novel Vignition spark-plug having a central positive electrode, a grounded negative electrode, and an interinediateelec- I l5trode in novel relation to the positive and negative electrodes, whereby aplu-ralityA of spark-gapsfin series are provided, all located Within the firing chamber ofthev engine cylinder Withuvvhich the-spark-plug is connected7 so that not only are greatly intensified sparks obtained, but` tatsparks under high engine compression are assured.

The invention has for Va t rther objectto providesuch a novelconstruction andarrangementof the electrodes of 7aspark-'plug that thetiring points are all projected into theV interior of the tiring chamber of the engine cylinder so that-they are subjected to lthe. iniuence's. o1 the hot temperatures at- .ai

4lect-ion otoilfor'so'ot 'at 4the tiring points of the electrodes is substantially eliminated .so lthat ouling'ot the plugs by oil or soot or the Aformation of carbon, tending to render the Same inoperative, is avoided." V Otherobjects and advantages of this invention','not at this time more particularly enumerated,` Will be clearly understood `from Y the following detailed description of Vthe same. y 4

The invention is clearly illustrated in the accompanying drawings, in vvhich1V Figure 1 isv a side elevation of 'the novel sparkplug made according to and embodying theprinciples of this invention; Figure 2 is a part longitudinal vertical section ofthe same With the core and intermediate electrode shownin elevation; Figure 3 is 'acomplete verticallongitudinal section of the 501 same ;,'Figure1'is.a lower end elevation (of-the 4samel iut drawn on' an enlargedscale; and Figure 5 is a horizontal transverse section Mr""f`taken on line iii'V Figure Y1, andv also drawnbn' an enlargedv scale.

, chamber 1, open at its upper end' andfintei`- .70

A f shan'aber 5,] open atv the lower end of said portion 2. The upper side of said 4vannular kshoulder 3 provides a seat fforj supporting. v the detachable porcelain:insulator 'corew'lVY` 'the'lowerl side of` which is supported upon `tained in theA latter, with the Vresult that colthe usual manner. Said porcelain core? is I assembled relation to said main body by *meansfof an 'externally threaded union 11, vwhich' is screwed into the internally' threadled chamber .f1 so as to engage'the upperside vpreferably made of manganese nickel, Which 95 .ally through said porcelain core 7, with its y `1 "provided with 4beaded threads '1,6'. for co` jecting upwardly Vfromthe cap 15 is' ascrewbinder nut. 18 for holding anelectric eur- .V

nen'ewe'd "Api-i1 141,; 1927.1l

Similar characters 'of' reference' are .einployed in all of thel hereinabove'described c v views to indicate y,co rresplendingf partsf-` n i Referring' noiv to .saiddrawings, the' r'eference character 1 indicates`l 'thef main body of the-'fspark-plug,which is provided' at vits lower end with, an externally threaded' por tion 2, by means of which the yspark-plug is operatively connected With the engine cylinder itis to .s'erve.` Saidmain A body 1 is r.also provided with the ,usual` longitudinal 65 opening extending therethrough from'end to end, and intermediate the ends 'of Wliichkis disposed an` internal annular, shoulderl '8 which divides said 'opening vinto an"up`per nally threaded at Said open end, 'and a lotv'er which in turn supports the positive electrode i Sfothe spark-plug.A 'Said porcelainvcore- 7 is providecbat a suitablepoint intermediate its upper and 'lower end port-ions, vwith V'an annularv enlargement or external 'shoulder' 9,

said seat 6.' Asuitable gasketflO is interposed' between said shoulder9 andsaid seat in secured against Adisplacement",from normal S5 ot said enlargement or shoulder 9 o fsaid 90 porcelain core. -A suitable gasket 12 is in-J terpose'd between .the union 11 and-saidenlargement or shoulder9 in the usualk manner. SaidV positive electrode comprises a rod,

is disposed to lextend longitudinally or a'Xilower free end 1 3 vprojecting downwardlyh beyond the lowerA extremity of said core. rIlie upper end portion of said core 7 is provided with an externally threaded stud 14, preterablyof reduced diameter. Engaged upon said stud 111 is atermi'nal 'cap 15, `Which acting with the threads Ao''said stud 14. Pro, '105 threaded post 17 /upon which iss-'engaged av n rent supply wire in velectrical connection with ysaid cap. VThe upper endV of said positive electrode 8 extends into the body of said cap 15y soaslofboth electrically and mechanically connect the one Withrthe other. The

`upper extremity of. the core Z is Vprovided with a depressed or dish-shaped cavity 19 `which affords a receiving space for a suitable ,cement l2O whereby the cap is held against accidental "loosening andYdisplacey ,ment ,fromA the cre. i The cement will ,also n Work into the* cavities intermediate f the threads of the stud 14; and thefbeaded threads 16 of the cap 15, so las to' afford an addi- '1 tionaly binder between'the'caip and the core.

;"l",he negative electrodeof the spark-plug is connected :with the lower extremity of the A'portion2of saidmain 1 so asto be lgrounded electrically therewith,l and the f same 'comprises an annulary terminal member yorfring 21 which i'sdispose'd in concentric v`relation to and spaoede'outvvardly from the lower free end 13 of the positivel electrode 8.

Said ring 21'is vsupported by an A'inverted conical-'flangaportion 22, the body vof which A is cut-away tojprovide a plurality ofvent openings 23;` Said lower extremity of the portionk2 yof said main bodyl is provided with` anfannular 'retainingv flange 24., within ,the embrace iof which the upper marginal portions 25 of'sa-id'angap'ortion 22 is envrthrough theloWer chamber 5 ofthefmain Yopen end of. the latter.

fgagedMWliereupon said retaining fiange` `24 isturned or clenched laround the flange-portion'22,`tovthus mechanically ailix saidfnegative electrodeto thespa'rk-p'lug body yWliile at the same time. electrically groundingthe negative electrode -upon said? vmainv body. lSaid negative electrode 1s preferablyy made Y of kmanganese nickel. Y A

' Saidporcelain core`7 is'so disposed fthat its `lower portion projectsA vdownwardly *bodyV 1 but terminates shorty of the lower said lower, portion of the core 'Z Vis provided with anannular shoulder or enlargement 26.

I The referencecharacter 27 indicatesthe main body o'fyan intermediate electrode, said main body being preferably'of tubular form ,andl

*taperingv toward yits .lower end.Y Inte'grally connectedfjvith the upper endof said 'main Y bodyA 27 is-arferrule; member 28 whichA is .mounted upon the shoulder or enlargement `26 of the core, whereupon' thelrupper lmargir-nal portion o fsaidV ferrule lmember`28 is turned inwardly ror'clenched overy the yupper side of said shoulder 0r enlargement 26, to

1 thus,securely support theeintermediate electrodefin operative assembled relation. The

yterminal portions of the electrodes.V

The extremity of neeefiee said lower end of said mainY body 27 of the intermediate electrode are a plurality of outwardly deflectedfradial terminal projections 30, theends of which are' opposed to and inwardly space-d relative to the ring-like termiynal of saidnegativeeleCtrOde 21, to thereby provide intermediate said projections 30 and ring "21 additional spark-gaps 31 1n series relation to the spark-gap 29. The maln body 27 of said intermediate-,electi'odeiis cut away at suitable points to provide vents32.

Saidv intermediateV electrode is. insulated by the core '-7 from both the positive fandnegative electrodes of thev spark-plugpandvthe same is also preferably made of vmanganese nickel. Y l

In operation'the novel :construction of the ,spark-plug above described functionsjin the following manner f Thecurrent is supplied to timed relation to the piston strokes Within the r engine cylinder With ywhich it is connected. Then the vaporized fuel is introduced into theV engine cylinder vand compressed by the compression stroke of the piston, the same isf'caused to flow through the vents 23l and 32V so as tojsurroimdV the electricalcurrent isv thereupon causedto enter,l the positive electrode 8",v Whereuponjit immediately jumps the gap 29to` the inter- Vmediate electrode, and thence jumps from lthe terminal projections BO' 'across vthe vgaps 31 to the negative yelectrode 21'. 4 The gaps f 29and 3 1 being in series,v the electrical veffect" is to greatly intensify the' sparks 'or electrical arcs produced, thusassuring atleast rtvvo' in tenseand hot blueivfliite sparks or flashes, both of Which` are leEvectiveHi-n assuring. the

Vprompt and thorough ignitionfy of `the, fuel charge' compressed inthe engine cylinder.l Owing toA the'great intensityr` ofthe sparks produced, Vand the electrical'force of 'the `same as they strike across thespark-'gaps, the samewvill not be `impeded by the highpressures resultant v,upon the'lcompre'ssion' of the fuel.. Another advantage1 of thenovel arrangement of electrodesproviding',a plurality of` spark-gaps in the firing' chamber of vthe engine cylinder, is Athat ,thev disposition of the electrode terminals is such that they are projected into the said Vfiring'cham-v ber so that'uponrignition of'thjefuel theyare l c v, induced V- by the fuel, combustion',. and cfens'e'quently subjected to the high temperatur 'collection ofjoilfor soot fon'theterniinalsfjs 'substantially veliminated, so jthat' the Aterminais are maintained bright andp-cleali,

Another advantage of my novel/'arrangel ment of-electrodes to provide 1apl'urality of spark-gaps in series,"is that sho'rtcircuiting yof the *plug terminals is less likely to occur, *for if, under exceptienalcircumstances one gap should be closed'or"shortcireuite'd and n the positive lelectrode vin the usualmanner `and in proper The yEx 

